Crossflow oil pumps

[LancasterBob]

Just been donated an oil pump for a crossflow, and was told it's a high pressure/flow model. Any distinguishing features / stampings on the pump that would confirm this?

[Roger King]

You can't really tell a high pressure pump because it is completely standard apart from having a heavier relief valve spring. This is internal and the only way to tell would be to take the spring out and compare it to a known standard one.

 

A high capacity pump usually runs a deeper end plate to allow room for a bigger rotor set. Again, it is basically a standard pump, but the flat steel end plate is removed and replaced with the deeper version. If your end plate (held on with three screws) is approx 6mm thick it will probably be standard, but if it is more like 15mm thick it is likely to be high capacity. Beware of the high capacity pumps that use an aluminium end plate - this plate takes the thrust from the rotors and will wear quickly if it is aluminium.

 

High capacity pumps are normally high pressure by default.

[Roger King]

You can't really tell a high pressure pump because it is completely standard apart from having a heavier relief valve spring. This is internal and the only way to tell would be to take the spring out and compare it to a known standard one.

 

A high capacity pump usually runs a deeper end plate to allow room for a bigger rotor set. Again, it is basically a standard pump, but the flat steel end plate is removed and replaced with the deeper version. If your end plate (held on with three screws) is approx 6mm thick it will probably be standard, but if it is more like 15mm thick it is likely to be high capacity. Beware of the high capacity pumps that use an aluminium end plate - this plate takes the thrust from the rotors and will wear quickly if it is aluminium.

 

High capacity pumps are normally high pressure by default.

[Roger King]

You can't really tell a high pressure pump because it is completely standard apart from having a heavier relief valve spring. This is internal and the only way to tell would be to take the spring out and compare it to a known standard one.

 

A high capacity pump usually runs a deeper end plate to allow room for a bigger rotor set. Again, it is basically a standard pump, but the flat steel end plate is removed and replaced with the deeper version. If your end plate (held on with three screws) is approx 6mm thick it will probably be standard, but if it is more like 15mm thick it is likely to be high capacity. Beware of the high capacity pumps that use an aluminium end plate - this plate takes the thrust from the rotors and will wear quickly if it is aluminium.

 

High capacity pumps are normally high pressure by default.

[LancasterBob]

Thanks for the speedy reply Roger! Haven't got the pump with me at the mo so will check when I get home. From memory it has some codes/numbers either cast or stamped into the pump body - anybody got any idea if these were common for both standard and high pres., or different for each type?

 

Thanks again Roger,

 

Rob

[Robster]

Can you get service parts like new rotors for the pumps? I am thinking about a dry sump pump..or should the unit be replaced for a new one?

[Brian Soper]

new parts for dry sump pumps are avaiable I used Burtons supplied rotors skew gear etc

 

 

[I.Mupferit]

Question for Roger.

 

Just out of curiosity and to prevent Bob running into potential problems really but I remember fitting a high capacity/ high pressure pump to a modified Lotus twin cam which I owned about 30 odd years ago.

I seem to remember being told to drill a hole (1/16" rings a bell) through the block in an indent on the oil pump mating face, the idea for which, I believe, was to provide spray lubrication on to the oil pump skew gear as it was running under an increased load.

Is that still the case?

 

Brent

 

[Brian Soper]

All old racing driver tales, I had a High pressure High capacity pump'wet sump' fitted on Lotus 51 and all the skew gear/ dist drive and gear cam all chewed up and I heard these stories . It was cause by fitting the New Kent oil pump I had run a Ford Standard pump for several years with No problems.

I contacted Burtons who said' If the skew gear is the correct one ie made of the correct steel hardened correctly you will have no problems ,the loading of a 5 port dry sump pump is higher and its not done to race engine and there is lots of all around the cam at ALL times'

Alway go to people who produce 'race parts' Minister Burtons etc Piper and Kent would probally not get my vote , but I have a Kent cam in my Seven

Who wants to talk REAL LOTUS CARS!!

 

 

[Taran Las]

Geoff Lofthouse & Myself asked this question about the additional drilling sometime back - fortunately Roger came to the rescue and said don't do it. If you perform a search of the archives (probably 18 months ago) more detail will be found.

 

Can't do links I'm afraid. - Title of post - Dry sumping x-flow supersprint.

Date 27th May 2001

 

Philip. D. Owen

Membership No. 3976

 

 

 

Edited by - taran las on 14 Nov 2002 11:56:52